Date: Tue, 7 Apr 2009 10:58:08 -0400
From: Christopher Faylor <cgf-use-the-mailinglist-please AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: All clear [was Re: [1.7]: For the love of god, don't update!]
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On Tue, Apr 07, 2009 at 12:31:29PM +0100, Dave Korn wrote:
>Corinna Vinschen wrote:
>> On Apr  7 00:12, Dave Korn wrote:
>>>Grepping through library symbols seems quite fragile when so many
>>>standard C library functions are permitted to be implemented as macros.
>>
>>I assume they use nm rather than grep.
>
>Sorry, I was just using the term in the extended sense of searching for
>something, rather than the specific meaning of invoking the grep
>executable.  (cf.  the verb "to google").
>
>>But maybe we should give up on such broken configure scripts?
>
>Well, I guess the answer as ever is "Just how common is this problem
>and how much upheaval would it cause to drop support as compared to
>trying to keep them working"?  I can't see any /fundamental/ problem in
>making these static libs work.  (It does make me wonder if it wouldn't
>be worth making this an integrated feature in LD and/or DLLTOOL, so
>that we can do it with BFD instead of having to programmatically
>hexedit the file with a script.)

We don't programatically hexedit the static libraries.  That was the
whole point of my speclib rewrite.  The libraries are generated using
dlltool.

>BTW, I've put this problem aside for a day or so while I finish off my
>weak symbols design, but I do promise to come back to it after that and
>analyze in detail exactly what is going wrong.
>
>(I said there didn't "appear" to be any overlap in the tables, but that
>was on the basis of a quick look at the headers in PEview etc., and not
>a full byte-by-byte dump of the tables.  I suspect it may yet turn out
>to be what's happening; the corrupt nature of the EXEs I was building
>mangled the debug info and meant I couldn't be sure of what I was
>seeing in the debugger, but it looked an awful lot like it was getting
>an unexpected error in response to attempting to seek back 16 bytes
>after reading the AR header magic, and this could happen for instance
>if the IATs were overwriting each other so that the syscall went to the
>wrong imported API from the DLL and ended up looking like some random
>syscall with invalid arguments).

If that's true that could point to an actual binutils bug.

cgf

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